Endoscopic Ultrasound Elastography for Evaluation of Lymph Nodes: A Single Center Experience.

Background and aim: The differentiation between malignant and benign lymph nodes (LNs) is important for tumor staging, for detection of prognosis, and for selection of the best treatment strategy in many cancers. On B-mode EUS, there are some known criteria that suggest the malignant nature of LNs; these criteria may be found in benign LNs. The aim of the work is to evaluate the effectiveness of elasticity score and SR to differentiate between benign and malignant LNs.

Patients and methods: The study was designed as a retrospective study that included 40 patients with abdominal or mediastinal LNs, either associated with primary masses or isolated, referred for EUS evaluation. Elasticity scores and SR were determined during the examination and finally, EUS-FNA was done at the end of the procedure.

Results: In this 2-years study, 40 patients were enrolled (24 malignant; 16 benign). There were 23 males and 17 females. Their mean age was 52.5 years (range: 28-77). ES alone had a specificity of 87.5%, sensitivity of 41.7%, PPV of 83.3%, NPV of 50%, and accuracy of 60%. Based on the ROC curve analysis results, the best cut-off level of SR to obtain the maximum area under the curve (AUC) was 6.7 with a specificity of 99.9%, sensitivity of 57.1%, PPV of 99.9%, NPV of 64%, and accuracy of 77.5%.

Conclusion: The use of elasticity score and SR increases the reliability of differentiation between benign and malignant LNs and can decrease the number of unnecessary biopsies.